The Fraser Panel has identified as a priority for 2015 SEF Projects to examine factors that may explain or predict en-route losses in Fraser River sockeye. This is in response to impacts associated with the growing uncertainty in predicting migration mortality of Fraser sockeye as overall levels of en-route losses increase (mainly in association with higher river temperatures Patterson et al. 2007 a,b). Because fishing plans are adjusted to account for expected levels of en-route mortality, this has affected not only the achievement of spawning escapement targets but also the achievement of catch goals for U.S. and Canadian fishers in all sectors. Furthermore, harvest and escapement goals are made at the level of the four management groups but en-route losses can vary considerably at the stock level. These problems became acute and costly in 2013, when models used to predict en-route losses were accurate for a single-stock management group, Early Stuart, but not for the more abundant multi-stock Summer-run management group.
The en-route loss model that relies on simple inputs of temperature and flow from a single location grossly overestimated en-route loss of Summer-run fish in 2013. This overestimation of loss led to missed harvest opportunities for First Nations, commercial and recreational fishers from both Canada and the United States. In 2014, extensive debate continued over the use of simple environmentally-based models for predicting loss for all management groups, reminding us that this issue will not abate. The recent challenges faced by the Fraser Panel to make decisions regarding harvest adjustments to compensate for expected levels of en-route loss have highlighted the pressing need to re-examine the factors used to understand and describe en-route loss and the modelling work used to predict these losses.
We propose to address this priority by focusing on three main areas: 1) update and refine the current DNA-based stock assessment information needed for future modelling; 2) improve the existing management group-based en-route loss models (i.e., Management Adjustment models); and 3) expand the work to include new research on migration biology for individual stocks and explore alternative methods for applying this information to management.
S16-I03 & S15-I11 Improvements to predicting en-route loss estimates for Fraser Sockeye 2015-16
With increasing pressure to ease fisheries restraints on Interior Fraser River (IFR) Coho, a new emphasis must be placed on better exploitation rate (ER) estimates. There is limited hatchery capacity for coho coded wire tag (CWT) smolt production in the IFR and that capacity is currently split between two systems in the Thompson River complex whereby the Coldwater and Eagle Rivers both receive approximately 60,000 smolts per year. The works proposed here will strengthen the current Coldwater CWT indicator stream assessment.The Coldwater River coho program has been an indicator for IFR coho since 1987 and also benefits from the Nicola Tribal Association’s (NTA) Aboriginal Fisheries Strategy (AFS) enumeration activities including area under the curve (AUC), DIDSON operations, and carcass recovery. Current Coldwater indicator program involves a system escapement estimate using AUC and DIDSON technology. Carcass recovery is used to determine adipose fin clip (AFC) and sex ratios. We propose to enhance the existing program to obtain greater certainty around both the escapement estimate and AFC ratios of IFR coho in the Coldwater River thereby providing greater certainty around the CWT ER of IFR coho.
S19-SP35 Coldwater River Adult Coho Enumeration 2019 Report
S18-SP06 Coldwater River Adult Coho Enumeration
S17-I29 Coldwater River Adult Coho Enumeration
S16-I16 Coldwater River Adult Coho Enumeration Report 2016
The 2005 Pacific Salmon Commission (PSC) Report of the Expert Panel on the Future of the Coded Wire Tag Recovery Program for Pacific Salmon (PSC Tech. Report No. 18) identified shortcomings of coho indicator stocks due to low tag recoveries (Hankin et al. 2005). With the prolonged low marine survival rates of Southern B.C. (SBC) coho and subsequent reduction in fisheries, the coho stocks in SBC fail to obtain sufficient recoveries of coded-wire tags (CWTs). In addition to the increased sampling already implemented as part of the CWT improvement program directed towards coho, increasing the number of CWT’s applied to coho will provide better information regarding marine survival, distribution and exploitation rates of SBC coho.
S18-SP10 Increased Hatchery Production and Coded Wire Tagging of Interior Fraser Coho
S17-I12 Increased Hatchery Production and Coded Wire Tagging of Interior Fraser Coho
S16-I24 Increased Hatchery Production and Coded Wire Tagging of Interior Fraser Coho Report. Year 1 of 3
The 2005 PSC Report of the Expert Panel on the Future of the Coded Wire Tag Recovery Program for Pacific Salmon identified shortcomings of coho indicator stocks due to low tag recoveries. With the prolonged low marine survival rates of Southern B.C. (SBC) coho and subsequent reduction in fisheries, the coho stocks in SBC fail to obtain sufficient recoveries of coded-wire-tags (CWTs). In addition to the increased sampling already implemented as part of the CWT improvement program directed towards coho, increasing the number of CWT’s applied to coho will provide better information regarding marine survival, distribution and exploitation rates of SBC coho. This project proposes to increase CWT application at 4 hatchery stocks to provide this information to analysts and fishery managers.
S19-SP18 Increased CWT application in Southern B.C. coho indicator stocks 2019 Report
S18-SP25 Increased CWT application in Southern B.C. Coho indicator stocks
S17-I08 Increased CWT application in Southern B.C. coho indicator stocks
S16-I02 Increased CWT application in Southern B.C. coho indicator stocks report 2016. Year 2
S15-I10 Increased CWT Application in Southern B.C. Coho Indicator Stocks 2015
The assessment of the daily abundance of Fraser River Sockeye and Pink salmon are based on hydro-acoustic data collected at Mission. Marine test fishing catches are used as early indicators of relative abundances in marine areas, but need to be extrapolated using an expansion line (1/catchability) to derive abundance estimates, but because of the high variability in marine test fishing catchability and the uncertainty in the expansion line, the resulting abundance estimates will vary widely.
An important factor that impacts catchability is local tides and currents; however, it has not been possible to explain some of the variability in catchability data using published tide and current information, as it does not take into account the real-time localized tidal impact and currents on salmon migration behaviour at specific test fishing locations.
This project aims to collect local real-time tide and current information over three years and evaluate its usefulness to improve abundance estimates derived from marine test fishery data. The collection of these data will augment other test fishery data used to assess run sizes.
S18-FRP05 Collection of Local Tide and Current Data to Explain Variability in Marine Catch Data and Improve Daily Abundance and Run Size Estimates of Fraser River Sockeye & Pink Salmon
S17-I04 Deployment of ocean surface current trackers in upper Johnstone Strait
S16-I10 Collection of local tide and current data to explain variability in marine catch data and improve daily abundance and run size estimates of Fraser River Sockeye and Pink salmon Report 2016
Since 2007, with support from the Southern Boundary Restoration and Enhancement Fund, calibration work has been conducted on twenty-five Sockeye populations of various stream types in the Fraser and has led to the development of indices for aerially surveyed Sockeye populations on the following three stream types: i) medium sized, clear streams, ii) medium sized, partially turbid/tannic streams and iii) large sized, clear streams. Although this represents substantial progress, significant gaps still exist on the remaining stream types and lake spawning populations. Calibration work involves the comparison between estimates generated using high precision enumeration techniques (enumeration fences, sonar, and/or mark-recapture programs) and those generated using standard low precision visual techniques. As annual calibration opportunities on target populations are limited, calibration work over the long term will be required to satisfy the data requirements for all stream types. The actual populations to be calibrated will be determined based on in-season estimates of abundance.
S18-FRP03 Calibration of Visual Assessment Methods for Fraser River Sockeye Salmon (Oncorhynchus nerka)
S17-I06 Calibration of Visual Assessment Methods for Fraser River Sockeye Salmon Year 9
S16-I21 Calibration of Visual Assessment Methods for Fraser River Sockeye Report 2016
S15-I01 Calibration of Assessment Methods for Fraser Sockeye Enumeration 2015. Year 7
S14-I02 Calibration of Assessment Methods for Fraser Sockeye Enumeration 2014. Year 6
S13-I01 Calibration of Assessment Methods for Fraser Sockeye Enumeration 2013. Year 5
S12-I02 Calibration of Assessment Methods for Fraser Sockeye Enumeration 2012. Year 4
S11-I04 Calibration of Assessment Methods for Fraser Sockeye Enumeration 2011. Year 3
S10-I05 Calibration of Assessment Methods for Fraser Sockeye Enumeration 2010
S07-I05 Calibration of Assessment Methods for Fraser Sockeye Enumeration 2007
This project proposes to analyse the relationship between sockeye and pink salmon abundance and existing CPUE data from Canadian purse seine ITQ fisheries, years 2010-2014. This will entail: 1) obtaining catch data by set and location from individual purse seiners in Area 12 and comparing with indices of abundance by area. 2) Examining the special case situation in Area 29 where ITQ seiners have fished on delaying Fraser River sockeye (2010, 2014) and pink salmon (2013). 3) Exploring evidence for density dependence catchability in the ITQ fishery dynamics. 4) In consultation with PSC Staff, incorporate the above (if useful) within a Bayesian hierarchical methodology. 5) Review compliance with the requirements identified in the Kowal Letter to the Fraser River Panel (2002) and also with the Run-size estimation workshop (2003). And finally, 6) Develop a plan for additional sampling opportunities for the Panel’s consideration for implementation in future years.
S16-I19 Analysis of existing CPUE data from Canadian Commercial ITQ fisheries for the purpose of the possible integration of this information into run-size models for Fraser River sockeye and pink salmon
While Fraser River sockeye salmon survival has declined over the past decade, it has also exhibited high interannual variability. The processes responsible for this trend and the variability are not understood and require investigation. This project builds on the previous work by adding a fifth year of sampling juvenile migrants immediately prior to their entry into the Strait of Georgia (SoG). The sampling platform will be identical to that employed successfully in 2013-2015, and GSI analysis will help to provide estimates of relative abundance and migration timing past Mission by stock. It is anticipated that sampling intensity in 2016, a juvenile Pink Salmon outmigration year, will be similar to that in 2014. In 2016, we propose to repeat the 2014 & 2015 study design and parameters assessed, including the assessment of the nocturnal migration patterns of Sockeye juveniles for a third year.
As in previous years, samples collected under this project will be compared to samples collected in other ongoing and proposed assessments, such as DFO’s annual SoG trawl survey occurring June-July and a similar trawl survey in Johnstone Strait. In combination, these three studies will add a third year to a comprehensive multi-stock assessment of Fraser River juvenile sockeye salmon relative abundance and condition, from nursery lake exit through early marine near-shore residency.
Sub-yearling ocean-migrant sockeye salmon (e.g. Harrison River stock) can be important contributors to Fraser River Sockeye production. The 2016 survey will continue to incorporate the bio-sampling of captured sub-yearling juveniles to identify their contribution, and migration timing at Mission by Conservation Unit (CU).
Lastly, the 2016 project will explore the feasibility of deploying an acoustic Doppler current profiler in an attempt to measure water current velocities over a depth range. This information may be important in determining absolute juvenile sockeye abundance at Mission.
We propose to enumerate total Fraser River chum salmon escapement by conducting a high precision enumeration project on Chilliwack River escapement (e.g. mark-recapture or DIDSON) and combining the result with the ratio of Chilliwack chum to the total Fraser chum captured in the Albion test fishery. The proportion of Chilliwack chum at Albion will be determined using GSI on tissue from scale samples already collected during the test fishery.
This project will improve our ability to provide accurate spawning escapement estimates for Fraser River chum salmon. Accurate estimates are important to all aspects of Fraser River chum salmon management including annual stock run reconstruction, production forecasting, in-season terminal abundance estimates, the evaluation of management decisions/actions, and harvest sharing.
S17-I26 Albion-based estimate of total Fraser River Chum Salmon escapement using GSI at Albion and enumeration of Chilliwack River Chum Salmon escapement, PRESENTATION 2017
S16-I23 Albion-based Estimate of Fraser River Chum Escapement Using GSI and Estimate of Chilliwack River Chum Escapement Interim Presentation 2016
In 2014, Fisheries and Oceans Canada proposed a 3-year program to evaluate the effect of smolt size and age on the migration timing of Fraser River Sockeye Salmon out of the Strait of Georgia by conducting a weekly sampling program in southern Johnstone Strait with a purse seine. We proposed to use DNA analyses to infer stock-specific migration timing through this area and, combined with the sampling in the Lower Fraser River (Evaluation of abundance and stock composition of downstream migrating juvenile Sockeye Salmon in the lower Fraser River), provide accurate estimates of residence time within the Strait of Georgia at the Conservation Unit (CU) level. In addition, by examining changes in the relative abundance of different CUs between the lower Fraser River and Johnstone Strait, this study was expected to determine whether mortality rates differ among CUs within the Strait of Georgia. In addition, we proposed to assess the feasibility of using hydroacoustics as a tool to monitor how the abundance of juvenile Salmon changes over time in this area.
S16-I25 Migration timing of juvenile Fraser River sockeye in Johnstone Strait Interim Report 2016